Akai 1710W as a tube amp - UK Vintage Radio Repair and Restoration Discussion Forum

audionirvana · 7th Sep 2022, 3:07 am

Hiya, I’ve seen previous threads but not found anything that was complete and also seen YouTube videos so know it is possible.

I would like to extract the amp out of my Akai 1710. I took it apart yesterday but When I unplugged the small black connector that links up the amp to the tape path it would not power on at all. So I hooked it back up.

Next I connected my DAC to the line in on the akai and my phone to line in on DAC. Played some music but the sound coming out of the Akai with external speakers is barely audible.

Does anyone have some step by step advice on how they managed to achieve the task of using this as an AMP. The sound is loud and clear on tape playback but input source is barely audible

joebog1 · 7th Sep 2022, 7:58 am

Are you sure you want to ruin an Akai 1710 to make MP3 music ?.
In its day it was a very fine tape deck with many thousands sold ( in Australia alone ).

The amp itself is a VERY modest affair in the first place, producing something in the vacinity of 1
( one ) watt. It will not have significant bass!!.

With welcome to the forum, and my best wishes.

Joe

DMcMahon · 7th Sep 2022, 10:05 am

Do you get the same very low volume if you try headphones ?

David

Welsh Anorak · 7th Sep 2022, 10:21 am

You are using the amplifier to do something it wasn't designed for. You will need to set the machine to record in order to get a monitor output and maybe modify the muting circuit.

As Joe says, this amplifier won't give you any great improvement over a reasonable transistor amplifierr.
If you want the 'valve (tube) sound' I'd go looking for a dedicated valved amplifier which would avoid you having to use a (rather nice) tape recorder.

Analogue man · 7th Sep 2022, 10:24 am

The reason the amp would not work with the black connector disconnected is probably because the mains feed runs via that connector to the micro switch which is the end of tape sensor on the tape tensioner on the righthand side.

ms660 · 7th Sep 2022, 10:36 am

So far as I can make out from the schematic, for line in through to loudspeaker for both channels you would have to disconnect the output stage dummy loads (used in record mode) from the rec/playback switch contacts and connect the loudspeakers to those contacts instead, the record/playback switches being set to record.

Lawrence.

ms660 · 7th Sep 2022, 6:19 pm

Forgot to mention, bridge contacts 14 and 15 on both channels so that the tone control works, alternatively you could do the connection modifications at the front end by isolating record/playback switch contact 3 from the rest of the circuit and connecting the output (M) from the line in sockets from to that contact, ditto for the other channel, record/playback switch set to playback.

Lawrence.

audionirvana · 8th Sep 2022, 1:43 am

Thanks all for the suggestions. I have a technics RS1500 and the tape playback quality on the Akai is not the best so I barely use it now. Also can’t play 10” reels.

Diabolical Artificer · 8th Sep 2022, 7:15 am

As others have said you might be better making a little line stage amp, John Broskie' s CCDA amplifier is easy to build and would do the job, he also does PCB's, see - https://www.tubecad.com/2009/03/blog0161.htm & https://glass-ware.stores.yahoo.net/cclistki.html

Andy.

audionirvana · 8th Sep 2022, 9:55 am

Quote:

Originally Posted by joebog1

Are you sure you want to ruin an Akai 1710 to make MP3 music ?.
In its day it was a very fine tape deck with many thousands sold ( in Australia alone ).

The amp itself is a VERY modest affair in the first place, producing something in the vacinity of 1
( one ) watt. It will not have significant bass!!.

With welcome to the forum, and my best wishes.

Joe

Who said anything about mp3 fyi I was intending to hook it up to my zen tidal streamer to play high quality mqa

audionirvana · 8th Sep 2022, 11:44 am

Quote:

Originally Posted by DMcMahon

Do you get the same very low volume if you try headphones ?

David

Hey David actually when the source is plugged into line in on the Akai and I switch record mode on. I get lovely clear sound from headphones just no sound from the external speakers 1/4 jack

ms660 · 8th Sep 2022, 11:57 am

The loudspeakers are switched out in record, the loudspeakers impedance is substituted by the 10 Ohm dummy load resistor R016 and its counterpart in the other channel (see Post#6 etc)

Lawrence.

audionirvana · 8th Sep 2022, 5:07 pm

Quote:

Originally Posted by ms660

The loudspeakers are switched out in record, the loudspeakers impedance is substituted by the 10 Ohm dummy load resistor R016 and its counterpart in the other channel (see Post#6 etc)

Lawrence.

Thanks yeah I saw your answer before was just pointing out the headphones worked. Thanks for that advice

joebog1 · 8th Sep 2022, 9:51 pm

Quote:

Originally Posted by audionirvana

Quote:

Originally Posted by joebog1

Are you sure you want to ruin an Akai 1710 to make MP3 music ?.
In its day it was a very fine tape deck with many thousands sold ( in Australia alone ).

The amp itself is a VERY modest affair in the first place, producing something in the vacinity of 1
( one ) watt. It will not have significant bass!!.

With welcome to the forum, and my best wishes.

Joe

Who said anything about mp3 fyi I was intending to hook it up to my zen tidal streamer to play high quality mqa

I hate digital

So to me it is still playing MP3

Joe

paulsherwin · 8th Sep 2022, 11:03 pm

Please stay on topic.

MP3 is a lossy codec and nothing to do with digital encoding in itself.

audionirvana · 9th Sep 2022, 4:40 am

Quote:

Originally Posted by joebog1

Quote:

Originally Posted by audionirvana

Quote:

Originally Posted by joebog1

Are you sure you want to ruin an Akai 1710 to make MP3 music ?.
In its day it was a very fine tape deck with many thousands sold ( in Australia alone ).

The amp itself is a VERY modest affair in the first place, producing something in the vacinity of 1
( one ) watt. It will not have significant bass!!.

With welcome to the forum, and my best wishes.

Joe

Who said anything about mp3 fyi I was intending to hook it up to my zen tidal streamer to play high quality mqa

I hate digital

So to me it is still playing MP3

Joe

Actually my mine listening source is vinyl but that said there are some artists who aren’t on vinyl so yeah. Anyway this is all just temporary as my main tube power amp malfunctioned, repair costs are too much and can’t afford a new one at least not for a couple of months. Since the akai is lying around thought why not use it since tape playback is a problem but with 96db speakers the 4W actually sounds really decent. Not blow your mind but decent.

audionirvana · 9th Sep 2022, 4:41 am

Quote:

Originally Posted by paulsherwin

Please stay on topic.

MP3 is a lossy codec and nothing to do with digital encoding in itself.

And yes exactly this and right on this is not about format wars

audionirvana · 9th Sep 2022, 4:43 am

Quote:

Originally Posted by ms660

The loudspeakers are switched out in record, the loudspeakers impedance is substituted by the 10 Ohm dummy load resistor R016 and its counterpart in the other channel (see Post#6 etc)

Lawrence.

The schematic shows R016 to be 8ohm was your 10ohm a typo ?

ms660 · 9th Sep 2022, 9:56 am

Quote:

Originally Posted by audionirvana

Quote:

Originally Posted by ms660

The loudspeakers are switched out in record, the loudspeakers impedance is substituted by the 10 Ohm dummy load resistor R016 and its counterpart in the other channel (see Post#6 etc)

Lawrence.

The schematic shows R016 to be 8ohm was your 10ohm a typo ?

It's shown as 10 Ohms in the schematic I have:

https://www.vintageshifi.com/reperto...ice-Manual.pdf

In the Akai 1710 the dummy load resistor is shown as 8 Ohms.

Lawrence.

DMcMahon · 9th Sep 2022, 11:23 am

Quote:

Originally Posted by audionirvana

Quote:

Originally Posted by DMcMahon

Do you get the same very low volume if you try headphones ?

David

Hey David actually when the source is plugged into line in on the Akai and I switch record mode on. I get lovely clear sound from headphones just no sound from the external speakers 1/4 jack

That is good and normal, the user manual states that for record monitoring to use headphones.

So it sounds like there is nothing wrong with the 1710W but as explained by others the speakers are muted/switched off during recording.

David

7th Sep 2022, 3:07 am	#1
audionirvana Triode Join Date: Sep 2022 Location: Singapore, Singapore Posts: 16	Akai 1710W as a tube amp Hiya, I’ve seen previous threads but not found anything that was complete and also seen YouTube videos so know it is possible. I would like to extract the amp out of my Akai 1710. I took it apart yesterday but When I unplugged the small black connector that links up the amp to the tape path it would not power on at all. So I hooked it back up. Next I connected my DAC to the line in on the akai and my phone to line in on DAC. Played some music but the sound coming out of the Akai with external speakers is barely audible. Does anyone have some step by step advice on how they managed to achieve the task of using this as an AMP. The sound is loud and clear on tape playback but input source is barely audible

7th Sep 2022, 7:58 am	#2
joebog1 Banned Join Date: Jun 2015 Location: Mareeba, North Queensland, Australia Posts: 2,704	Re: Akai 1710W as a tube amp Are you sure you want to ruin an Akai 1710 to make MP3 music ?. In its day it was a very fine tape deck with many thousands sold ( in Australia alone ). The amp itself is a VERY modest affair in the first place, producing something in the vacinity of 1 ( one ) watt. It will not have significant bass!!. With welcome to the forum, and my best wishes. Joe

7th Sep 2022, 10:05 am	#3
DMcMahon Dekatron Join Date: Apr 2019 Location: Worthing, West Sussex, UK. Posts: 6,604	Re: Akai 1710W as a tube amp Do you get the same very low volume if you try headphones ? David

7th Sep 2022, 10:21 am	#4
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,925	Re: Akai 1710W as a tube amp You are using the amplifier to do something it wasn't designed for. You will need to set the machine to record in order to get a monitor output and maybe modify the muting circuit. As Joe says, this amplifier won't give you any great improvement over a reasonable transistor amplifierr. If you want the 'valve (tube) sound' I'd go looking for a dedicated valved amplifier which would avoid you having to use a (rather nice) tape recorder. __________________ Glyn www.gdelectronics.wales

7th Sep 2022, 10:24 am	#5
Analogue man Hexode Join Date: Dec 2020 Location: Raunds, Northamptonshire, UK. Posts: 355	Re: Akai 1710W as a tube amp The reason the amp would not work with the black connector disconnected is probably because the mains feed runs via that connector to the micro switch which is the end of tape sensor on the tape tensioner on the righthand side. __________________ Graham

7th Sep 2022, 10:36 am	#6
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Akai 1710W as a tube amp So far as I can make out from the schematic, for line in through to loudspeaker for both channels you would have to disconnect the output stage dummy loads (used in record mode) from the rec/playback switch contacts and connect the loudspeakers to those contacts instead, the record/playback switches being set to record. Lawrence.

7th Sep 2022, 6:19 pm	#7
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Akai 1710W as a tube amp Forgot to mention, bridge contacts 14 and 15 on both channels so that the tone control works, alternatively you could do the connection modifications at the front end by isolating record/playback switch contact 3 from the rest of the circuit and connecting the output (M) from the line in sockets from to that contact, ditto for the other channel, record/playback switch set to playback. Lawrence.

8th Sep 2022, 1:43 am	#8
audionirvana Triode Join Date: Sep 2022 Location: Singapore, Singapore Posts: 16	Re: Akai 1710W as a tube amp Thanks all for the suggestions. I have a technics RS1500 and the tape playback quality on the Akai is not the best so I barely use it now. Also can’t play 10” reels.

8th Sep 2022, 7:15 am	#9
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,667	Re: Akai 1710W as a tube amp As others have said you might be better making a little line stage amp, John Broskie' s CCDA amplifier is easy to build and would do the job, he also does PCB's, see - https://www.tubecad.com/2009/03/blog0161.htm & https://glass-ware.stores.yahoo.net/cclistki.html Andy. __________________ Curiosity hasn't killed this cat...so far.

8th Sep 2022, 11:57 am	#12
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Akai 1710W as a tube amp The loudspeakers are switched out in record, the loudspeakers impedance is substituted by the 10 Ohm dummy load resistor R016 and its counterpart in the other channel (see Post#6 etc) Lawrence.

8th Sep 2022, 11:03 pm	#15
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,965	Re: Akai 1710W as a tube amp Please stay on topic. MP3 is a lossy codec and nothing to do with digital encoding in itself.